Real-time (RT) imaging, such as fluoroscopic imaging, is often used in minimally-invasive medical procedures, sometimes in conjunction with various three-dimensional (3D) imaging modalities. Several techniques deal with registration of RT images with 3D models and 3D maps of patient organs. For example, U.S. Patent Application Publication 2010/0022874, whose disclosure is incorporated herein by reference, describes an image guided navigation system that comprises a memory, a locator, a processor and a display. The memory stores a plurality of CT images and a software program. The locator is capable of indicating a direction to a surgical area, and the indicated direction of the locator is defined as a first direction. The processor is electrically connected to the memory and the locator. At least one corresponding image corresponding to the first direction is obtained from the plurality of CT images by the processor executing the software program. The at least one corresponding image comprises at least one simulated fluoroscopic image. The display is capable of showing the at least one corresponding image.
U.S. Pat. No. 8,515,527, whose disclosure is incorporated herein by reference, describes a method and an apparatus for registering 3D models of anatomical regions of a heart and a tracking system with projection images of an interventional fluoroscopic system.
U.S. Pat. No. 7,327,872, whose disclosure is incorporated herein by reference, describes a method and a system for registering 3D models with projection images of anatomical regions. A first image acquisition system of a first modality employing a catheter at an anatomical region of a patient is configured to produce a first image of the anatomical region using fluoroscopy, the first image comprising a set of fluoroscopy projection images. A second image acquisition system of a second different modality is configured to generate a 3D model of the anatomical region. An anatomical reference system is common to both the first and second image acquisition systems. A processing circuit is configured to process executable instructions for registering the 3D model with the fluoroscopy image in response to the common reference system and discernible parameters associated with the catheter in both the first and second image acquisition systems.